I'm hoping someone here might be able to offer some thoughts that I'm
overlooking. So I have a /22 that I use primarily to deliver customer
emails. We're an ESP, customers bring their own domains. I've been using
the first two /24s of the space for a while, but I'm trying to slip the
rest of the /22 into production. My plan was to do it slowly, so as to
not set off fire alarms at Microsoft, Verizon, and AT&T. However, I'm
only using one IP from the 3rd /24 so far, and I still can't get this IP
warmed up with Microsoft.
I'm at least two months into solid usage of that IP, and Microsoft is
still rejecting every mail from it with:
"550 5.7.1 Unfortunately, messages from [136.175.110.3] weren't sent.
Please contact your Internet service provider since part of their
network is on our block list (S3150). You can also refer your provider
to http://mail.live.com/mail/troubleshooting.aspx#errors.";
I'll turn around and deliver the same message from 108.0/24 or 109.0/24
and they'll accept it with no issue. They've given me temporary
mitigation at my request, it's expired and we're still doing this over
and over again.
Now I do filter outbound email heavily. Obviously customers use email
forwarders and some of what gets through isn't great, but it's not like
I'm flooding their servers with junk. Most of this is direct personal
emails between my users and theirs. There's no abuse complaints coming
in from MS, SNDS portal is as clear as can be. I'd argue that I'm the
most militant ESP when it comes to preventing outbound marketing, I'll
nuke a bad actor from orbit within an hour and everything is monitored
by human eyes and automation 24/7. Password compromises rarely make it
beyond the "testing the credentials" phase. All around very clean
outbound. And yet, here we are.
What do the rest of you do to warm up a new IP range with Microsoft, and
have you ever found yourself months into a new range with nothing to
show for it with them?
Jarland
MXroute
_______________________________________________
mailop mailing list
mailop@mailop.org
https://list.mailop.org/listinfo/mailop
